In recent years, there has been an increased demand for environmentally friendly techniques for manufacturing materials derived from non-petroleum sources. For example, researchers have been studying the feasibility of manufacturing biofuels, waxes, plastics, lubricants, polymers, and the like, using natural oil feedstocks, such as vegetable and seed-based oils. Metathesis reactions involving natural oil feedstocks offer promising solutions for today and for the future.
Natural oil feedstocks of interest include non-limiting examples such as natural oils (e.g., vegetable oils, fish oil, animal fats) and derivatives of natural oils, such as fatty acids and fatty acid alkyl (e.g., methyl) esters. These feedstocks may be converted into industrially useful chemicals (e.g., waxes, plastics, cosmetics, biofuels, etc.) by any number of different reaction mechanisms, including metathesis reaction mechanisms. Significant reaction classes include, as non-limiting examples, self-metathesis, cross-metathesis with olefins, and ring-opening metathesis reactions.
Depending on the level of unsaturation in the natural oil feedstock, esters and olefins produced from the refining process typically include levels of polyunsaturated components, potentially decreasing their market value or requiring additional processing (e.g., capital and operating costs) to upgrade their values. Additionally, the polyunsaturation in the oil may cause the formation of cyclohexadiene (CHD), which may lead to undesired levels of benzene, or the loss of desirable olefin products based on downstream separation processes. Therefore, it is desirable to improve the efficiency of the refining processes, and the reaction mechanisms and separation processes associated therewith.